JP2611776B2 - Emulsifier for emulsion polymerization - Google Patents

Description

Description: TECHNICAL FIELD The present invention relates to an emulsifier for emulsion polymerization, and more particularly to an emulsifier having a (meth) acryl group used for aqueous emulsion polymerization of an ethylenically unsaturated monomer.

Conventionally, emulsifiers for emulsion polymerization include anionic surfactants such as alkyl sulfates, alkyl benzene sulfonates, dialkyl sulfosuccinates, and polyoxyalkylene alkyl (aryl) ether sulfates, and polyoxyalkylene alkyl (aryl). )
Nonionic surfactants such as ethers, polyoxyethylene polyoxypropylene block copolymers, polyoxyethylene sorbitan fatty acid esters, etc. are used alone or in combination, but the stability of the emulsion and the production of emulsion The properties and the like of the film are not always sufficiently satisfactory, and many problems to be solved remain. That is, the polymerization stability of the emulsion, the mechanical stability of the obtained emulsion, the chemical stability,
There are problems in freeze-thaw stability, pigment miscibility, storage stability, and the like. In particular, mechanical stability still needs to be improved.

Furthermore, when a polymer film is prepared from an emulsion, the used emulsifier remains in the polymer film in a free state, and thus there are problems such as poor water resistance and poor adhesion.

Further, when the emulsion is destroyed by means such as salting out and the polymer is taken out, a large amount of emulsifier is contained in the waste water, which causes river pollution, so that a great deal of labor is required for the removal treatment of the emulsifier.

From such a viewpoint, in order to solve the problems of the conventional emulsifiers, a number of patents relating to novel emulsifiers generally called reactive emulsifiers have been proposed.

For example, as an anionic reactive emulsifier,
No. 12472, JP-A-54-144317, JP-B-46-34894, JP-B-56-29657, JP-A-51-30285, JP-B-49-4629
No. 1, etc., as a nonionic reactive emulsifier,
No. 6-28208, JP-A-50-98484, etc., which have been tried as emulsifiers for emulsion polymerization of various monomers, but when these reactive emulsifiers are used alone as an emulsifier, the stability during emulsion polymerization is reduced. In many cases, when used in combination with a conventional emulsifier, there is a problem that the original performance cannot be sufficiently exhibited, for example, polymerization does not proceed smoothly.

As described above, various attempts have been made, but at present, the above-mentioned problems have not yet been sufficiently solved.

The present inventor has arrived at the present invention as a result of intensive studies to solve these problems. That is, the present invention provides a compound represented by the general formula: Wherein R ₁ is an alkyl group having 8 to 30 carbon atoms, R ₂ is hydrogen or a methyl group, A is an alkylene group having 2 to 4 carbon atoms or a substituted alkylene group, and m is 0 or 1 to 10 Integer, n is an integer of 1 to 200, and M is an alkali metal atom, NH ₄ or an alkanolamine residue. ] It is intended to provide an emulsifier for emulsion polymerization, characterized by containing at least one compound represented by the following formula:

In the above general formula, R ₁ is an alkyl group having 8 to 30 carbon atoms,
For example, octyl, nonyl, decyl, undecyl, dodecyl, tridecyl, tetradecyl, pentadecyl, hexadecyl, heptadecyl, octadecyl, nonadecyl,
Eicosyl and the like. A mixture of these alkyl groups and the like may be used.

R ₂ is hydrogen or a methyl group.

A is an alkylene group having 2 to 4 carbon atoms or a substituted alkylene group, for example, ethylene, propylene, butylene, isobutylene, etc., which may be used alone, in a block or in a random mixture.

m is 0 or an integer of 1 to 10, preferably 0 or 1.

n is an integer of 1 to 200, more preferably in the range of 2 to 100.

M is an alkali metal atom such as sodium or potassium, NH ₄ , or an alkanolamine residue such as monoethanolamine or triethanolamine, and may be a mixture thereof.

Further, the emulsifier of the present invention can be easily produced industrially, and can be produced, for example, as follows.

That is, AOE X-24 [α-olefin oxide having 12 and 14 carbon atoms, manufactured by Daicel Chemical Industries, Ltd.] and acrylic acid are heated and reacted in the presence of a catalyst, and the obtained reaction composition is
Further, an alkylene oxide is added by a conventional method. Next, the emulsifier of the present invention can be obtained by sulfation with a sulfating agent such as sulfuric acid or sulfamic acid, and, if necessary, neutralization with a basic substance.

Examples of the monomer for emulsion polymerization to which the emulsifier of the present invention is applied include various monomers. For example, acrylic monomers such as acrylic acid, methyl acrylate, butyl acrylate, 2-ethylhexyl acrylate, methyl methacrylate, acrylonitrile, acrylonitrile, acrylamide, hydroxyethyl acrylate, and aromatic monomers such as styrene and divinylbenzene ,
Vinyl ester monomers such as vinyl acetate, vinyl chloride,
Examples include halogen-containing monomers such as vinylidene chloride, conjugated diolefin monomers such as butadiene, isoprene, and chloroprene, as well as ethylene, maleic anhydride, and methyl maleate. The emulsifier of the present invention can be used for emulsion polymerization of one or more of these monomers.

The polymerization initiator may be a conventionally known one, for example,
Examples include hydrogen peroxide, potassium persulfate, azobisibutylnitrile, benzoyl peroxide and the like.

Examples of the polymerization accelerator include sodium hydrogen sulfite, ferrous ammonium sulfate, and the like.

The emulsifier of the present invention is generally used in an amount of 0.1 to 20% by weight, more preferably 0.2 to 5.0% by weight, based on all monomers.

The emulsifier of the present invention alone can provide a good emulsion polymerization emulsion, but if necessary, another emulsifier or a protective colloid may be used in combination.

Emulsion polymerization emulsion obtained by applying the emulsifier of the present invention, for example, as an adhesive, a coating agent, an impregnating reinforcing agent,
It can be applied to wood, metal, paper, cloth, and other concrete.

Hereinafter, the present invention will be described specifically with reference to examples.

[%, Parts are by weight. Production Example 1 Acrylic acid was placed in a reaction vessel equipped with a stirrer, a thermometer, and a reflux tube.
108 g, hydroquinone 1 g, triethylamine as catalyst
1.5 g of AOE X-68 [α-having 16 or 18 carbon atoms]
Olefin oxide, manufactured by Daicel Chemical Industries, Ltd.] 252 g
Was added dropwise, and the mixture was stirred and reacted at 80 ° C. for 5 hours, followed by washing with water to remove excess acrylic acid.

Next, the obtained reaction composition was transferred to an autoclave, and 2 mol and 10 mol of ethylene oxide were added to the reaction composition at a temperature of 80 ° C.

Next, the above-mentioned 2-mol adduct of ethylene oxide was subjected to a sulfation reaction using sulfamic acid, and the resulting reaction composition was designated as emulsifier [A] of the present invention. The sulfate ester ammonium salt of a 10 mol adduct of ethylene oxide obtained by the same sulfation method was used as the emulsifier [B] of the present invention.

Production Example 2 129 g of methacrylic acid, 1 g of hydroquinone, and 1.5 g of triethylamine as a catalyst were charged into a reaction vessel equipped with a stirrer, a thermometer, and a reflux tube. , Manufactured by Daicel Chemical Industries, Ltd.]
After 196 g was added dropwise and the mixture was stirred and reacted at 80 ° C. for 5 hours, excess methacrylic acid was removed by washing with water. Next, the obtained reaction composition was transferred to an autoclave, and 5 mol of propylene oxide was added to the reaction composition at a temperature of 80 ° C.

Next, the above propylene oxide 5 mol adduct was subjected to a sulfation reaction using sulfamic acid, and the resulting reaction composition was designated as emulsifier [C] of the present invention.

Production Example 3 174 g of hydroxyethyl acrylate, 1 g of hydroquinone, and 2 g of boron trifluoride etherate as a catalyst were charged into a reaction vessel equipped with a stirrer, a thermometer, and a reflux tube.
342 g of 8 [α-olefin oxide having 2 to 30 carbon atoms, manufactured by Daicel Chemical Industries, Ltd.] is added dropwise, and the mixture is stirred and reacted at 80 ° C. for 5 hours. Hydroxyethyl was removed.

Next, the obtained reaction composition was transferred to an autoclave, and 30 mol and 100 mol of ethylene oxide were added to the reaction composition at a temperature of 80 ° C.

Next, the above ethylene oxide 30 mol adduct was subjected to a sulfation reaction using sulfamic acid, and the resulting reaction composition was designated as emulsifier [D] of the present invention. The ammonium sulfate salt of a 100 mol ethylene oxide adduct obtained by the same sulfation method was used as the emulsifier [E] of the present invention.

Example 1 The emulsifiers of the present invention [A] to
Emulsion polymerization was carried out using [E], and the physical properties of the obtained emulsion and the polymer film obtained from the emulsion were tested. For comparison, examples of conventional emulsifiers were also tested. The results are shown in Table 1.

[Emulsion Polymerization Formulation] 295 g of water and 5 parts of an emulsifier are dissolved, and the temperature is raised to 70 ° C. Next, 20 parts of monomer and 0.5 part of ammonium persulfate were added,
Pre-polymerization and 3 minutes after 10 minutes from the start of polymerization
Over time, 180 parts were added dropwise to carry out polymerization. Then, after aging for 1 hour at the polymerization temperature, the mixture was cooled, and the emulsion was taken out and used as a test sample.

Next, apply this test sample to a glass plate and
After drying for 24 hours, the dried coating film was heated at 110 ° C. for 3 minutes to prepare a polymer film.

Example 2 295 parts of water, various combined emulsifiers 5 shown in Table 3 as emulsifiers
Was melted, the temperature was raised to 80 ° C., and 20 parts of a mixed monomer of n-butyl acrylate / styrene = 7/3 as a monomer,
0.3 parts of ammonium persulfate was added, and the mixture was preliminarily polymerized. 180 minutes of the above-mentioned mixed monomer was dropped in about 3 hours from 10 minutes after the polymerization was started, and then aging was performed at 80 ° C. for 1 hour. After cooling, the emulsion was taken out and used as a test sample.

Further, the test sample was applied to a glass plate, dried at room temperature for 24 hours, and the dried coating film was thermally cured at 110 ° C. for 3 minutes to prepare a polymer film.

The physical properties of the emulsion obtained as described above and the polymer film obtained from the emulsion are described in the third section.
It is shown in the table. Table 2 also shows examples of conventional emulsifiers as comparative products.

Example 3 Emulsions obtained by emulsifying the emulsifiers [A], [F], and [G] of the present invention with the emulsion polymerization formulation of Example 1 and polymer films obtained from the emulsions Was tested for physical properties. The results are shown in Table 3.

Claims (1)

(57) [Claims] (1) a general formula, Wherein R ₁ is an alkyl group having 8 to 30 carbon atoms, R ₂ is hydrogen or a methyl group, A is an alkylene group having 2 to 4 carbon atoms or a substituted alkylene group, and m is 0 or 1 to 10 Integer, n is an integer of 1 to 200, and M is an alkali metal atom, NH ₄ or an alkanolamine residue. ] An emulsifier for emulsion polymerization, comprising at least one compound represented by the following formula: